To solve the problem of quantization noise in OFDM systems

a study on a novel quantization noise shaper for multi-carrier signal is presented. The paper first compares the applicability of two kinds of sigma-delta modulators with the single zero and multiple zeros. Then it gives the complete scheme

theory and simulation analysis of the multi-zero sigma delta modulator for OFDM systems. Studies show that the multi-zero sigma delta modulator without oversampling can effectively reduce the quantization noise in OFDM systems

and performs better in noise shaping. Under the conditions of 3bit quantization and 6dB SNR

the bit error rate of the system deceases by 3 order of magnitude. But limited by the non-cyclic quantization noise structure

the proposed modulator cannot achieve the ideal state of eliminating the quantization noise completely.